Neuro

Question 1

CNS nueotransmittr that is stimulant

Answer 1

Glutamate receptor agonism results in the flow of cations across a channel. With this flow of sodium (and in some cases calcium) into the cell, and potassium out of the cell, the resting membrane potential of the cell changes and thus generates an action potential. GABA is a major inhibitory neurotransmitter in the CNS, which in the case of the GABA-A receptor, opens chloride channels, hyperpolarizing them and making the generation of action potentials

Question 2

Agonism of opioid receptors causes

Answer 2

Opioid receptors result in increased potassium and decreased calcium conductance, thus decreasing the resting potential and resulting in hyperpolorization.

Changing the resting potential to be more negative, not the threshold potential (in other words, generation of an action potential still requires a certain positive inflection of mV, its just starting from a more negative point).

Question 3

Which of the following processes account for the greatest amount of brain energy consumption:

Answer 3

Among all the cellular processes of the brain (maintenance, transportation, metabolism, synaptic transmission), electrical activity (transporting ions across the cell membranes to maintain a resting potential and fire action potentials) is the largest consumer of energy.